Position of Vocal Cords in Quiet Respiration in Man, fyc. 403 



Whether the carcinoma which, follows in certain cases of Paget's 

 disease is caused by these organisms, which presumably produce the 

 cutaneous lesion, remains open for future investigation, as does also 

 the question whether there are in cancerous tumours generally para- 

 sites of the same, or of an allied, nature, but which from their simi- 

 larity to the cells of the infected tissues have hitherto escaped notice. 



"Oil the Position of the Vocal Cords in Quiet Respiration 

 in Man and on the Reflex-Tonus of their Abductor Muscles." 

 By FELIX SEMON, M.D., F.R.C.P., Assistant Physician in 

 charge of the Throat Department of St. Thomas's Hospital, 

 and Laryngologist to the National Hospital for Epilepsy and 

 Paralysis, Queen Square. Communicated by Prof. VICTOR 

 HORSLEY, F.R.S. Received May 25, Read June 12, 1890. 



Although the laryiigeal phenomena attending the act of respiration 

 in man have not escaped the attention of physiologists and laryngo- 

 logists, yet investigation on this point has been comparatively 

 limited and nothing like unanimity of views has been obtained. Oil 

 the contrary, a perusal of the chapters devoted to the description of 

 the mechanism of respiration in the admittedly best and most recent 

 physiological text-books shows that there exists a very remarkable 

 diversity of opinions, not merely on details or on points of secondary 

 importance, but on the very question, whether the larynx plays an 

 active rule during quiet respiration in man or not. 



Thus Hermann,* Dalton,t Landois, and Stirling;}; describe the 

 glottis in man during quiet respiration as in a condition of rhythmical 

 widening and narrowing ; Griitzner as forming a small triangle not 

 differing considerably from that seen after death, the laryngeal 

 muscles being in a state of inaction; Rosenthal|| as being pretty 

 widely open, this being due to some muscular action, not precisely 

 described ; Michael Foster^" as sometimes in a state of rhythmical 

 widening and narrowing and sometimes in the same state as seen 

 after death, this being due to an equilibrium between the dilating 



molluscum contagiosum is a disease due to the presence of Psorozoa ; and both 

 Darier and White, of Boston, have described similar Protozoa as being the essential 

 cause of a rare form of skin disease, which has been named " keratosis i'ollicularis " 

 or " psorospermosis folliculaire vegetante." 



* ' Physiologic,' 1870, p. 156. 



t ' A Treatise on Human Physiology,' 1867, p. 223. 



J Hermann's ' Handbuch dcr Physiologic,' vol. 1, Part ii, p. 57, el teq. 



' A Text-book of Human Physiology,' 2nd edit., vol. 1, p. 252. 



|| Hermann's ' Handbuch der Physiologic, vol. 4, Part ii, pp. 231, 232. 



1f ' A Text-book of Physiology,' 1889, p. 548, and 1879 (3rd edit.), p. 604. 



